Apparatus and method for instant on ability

1. A system comprising:

voltage sensing logic to determine a first source voltage V first source that corresponds to a first source; and

a controller to receive an indication of V first source from the voltage sensing logic, and further to:

responsive to V first source >a first output voltage (V 1 ), select a first source first voltage regulator to input V first source and to provide V 1 ;

responsive to V first source >a second output voltage (V 2 ), select a first source second voltage regulator to input V first source and to provide V 2 ; and

responsive to V first source ≤V 1 , select a second source first voltage regulator to input a second source voltage V second source that corresponds to a second source, wherein V second source is substantially constant in time and V second source >V 1 , and to provide V 1 independent of the first source first voltage regulator and of the first source second voltage regulator.

2. The system of claim 1 , wherein the first source includes a rechargeable source.

3. The system of claim 1 , wherein responsive to V first source ≤V 2 the controller is to select a second source second voltage regulator to input V second source , wherein V second source >V 2 , to provide V 2 , and to deactivate the first source second voltage regulator.

4. The system of claim 1 , wherein V second source >an N th output voltage (V N ) and V N >V 2 , wherein N>2 and wherein responsive to V first source ≤V N the controller is to select a second source N th voltage regulator to input V second source and to provide V N .

5. The system of claim 4 , further comprising responsive to V first source >V N the controller is to select a first source N th voltage regulator to input V first source and to output V N and to deactivate the second source N th voltage regulator.

6. The system of claim 1 , further comprising a charging source, wherein responsive to V first source ≤V 1 , the charging source is to supply power to the first source, and wherein after power is provided to the first source and responsive to an increase in V first source to greater than V 1 , the controller is to select the first source first voltage regulator to output V 1 and to deactivate the second source first regulator.

7. The system of claim 6 , wherein responsive to V first source ≤V N wherein V N is an N th output voltage, N≥2, and V N <V max wherein V max is a maximum voltage of the first source, the controller is to select a second source N th voltage regulator to input V second source and to provide V N and the controller is to deactivate a first source N th voltage regulator, and the charging source is to supply power to the first source, and wherein responsive to an increase in V first source to greater than V N , the controller is to select the first source N th voltage regulator to input V first source and provide V N and the controller is further to deactivate the second source N th voltage regulator.

8. The system of claim 7 , wherein the first source N th voltage regulator and the second source N th voltage regulator are included in an N th composite regulator that is a switching regulator, wherein in a first mode the N th composite regulator is to input V first source and to provide V N , and in a second mode the composite regulator is to input V second source and to provide V N .

9. The system of claim 1 , wherein the second source first voltage regulator includes a switching regulator to input V second source and to provide V 1 .

10. The system of claim 1 , wherein the first source first voltage regulator comprises a first switching regulator to input V first source and to provide V 1 responsive to V first source >V 1 .

11. The system of claim 10 , wherein the first source second voltage regulator comprises a second switching regulator to, responsive to V first source >V 2 , input V first source and to provide V 2 .

12. A method comprising:

receiving, by control circuitry, an indication of a first source voltage V first source of a first source;

selecting, by the control circuitry, a first source first voltage regulator to input V first source and supply a first voltage (V 1 ) responsive to V first source >V 1 , and selecting by the controller responsive to V first source ≤V 1 a second source first voltage regulator to input from a second source a voltage V second source >V 1 wherein V second source is substantially constant, and to supply V 1 independent of the first source first voltage regulator; and

selecting, by the control circuitry, a first source second voltage regulator that is to input V first source and supply a second voltage (V 2 ) responsive to V first source >V 2 , wherein V 2 >V 1 and selecting by the control circuitry responsive to V first source ≤V 2 a second source second voltage regulator that is to input V second source and is to supply V 2 independent of the first source first voltage regulator and of the first source second voltage regulator, wherein V second source >V 2 .

13. The method of claim 12 , wherein the first source comprises a rechargeable source, further comprising responsive to V first source <V 1 determining to charge the first source.

14. The method of claim 12 , further comprising responsive V first source being greater than an N th voltage (V N ), wherein V N >V 2 , selecting by the control circuitry a first source N th voltage regulator that is to input V first source and is to supply V N , and responsive to V first source <V N selecting a second source Nth voltage regulator to input V second source and to supply V N independent of the first source first voltage regulator, the first source second voltage regulator, and the first source N th voltage regulator, wherein V second source >V N .

15. The method of claim 12 , wherein the second source first voltage regulator comprises a linear voltage regulator.

16. The method of claim 12 , wherein the first source first voltage regulator comprises a switching regulator.

17. A system comprising:

a first source voltage regulator module that includes a first source first voltage regulator to input a first source voltage V first source from a first source, and to supply a first output voltage (V 1 ) responsive to selection of the first source first voltage regulator by a controller, and further includes a first source second voltage regulator to input V first source and to supply a second output voltage (V 2 ) responsive to selection of the first source second voltage regulator by the controller, wherein V 2 >V 1 ;

a second source voltage regulator module that includes a second source first voltage regulator to input a second source voltage V second source that is substantially constant from a second source that is distinct from the first source and wherein V second source >V 1 and V second source >V 2 , and responsive to selection of the second source first voltage regulator by the controller, to supply the first output voltage V 1 independent of the first source first voltage regulator and independent of the first source second voltage regulator, and a second source second voltage regulator to input V second source and responsive to selection of the second source second voltage regulator by the controller to supply V 2 independent of the first source first voltage regulator and independent of the first source second voltage regulator; and

the controller to monitor V first source and to select the first source first voltage regulator to supply V 1 responsive to V first source >V 1 otherwise to select the second source first voltage regulator to supply V 1 , the controller further to select the first source second voltage regulator to supply V 2 responsive to V first source >V 2 otherwise to select the second source second voltage regulator to supply V 2 .

18. The system of claim 17 , wherein the first source first voltage regulator includes a first switching regulator to supply V 1 responsive to selection by the controller of the first source first voltage regulator.

19. The system of claim 17 , wherein the second source first voltage regulator includes a first linear regulator to supply V 1 responsive to selection by the controller of the second source first voltage regulator.

20. The system of claim 17 , wherein the first source voltage regulator module includes a first source N th voltage regulator and the second source voltage regulator module includes a second source N th voltage regulator, wherein N>2 and V N is an N th output voltage, wherein responsive to V first source ≤V N the controller is to select the second source N th voltage regulator to input V second source and to supply V N , and responsive to V first source >V N the controller is to select the first source N th voltage regulator to input V first source and to supply V N .